To reiterate: catcodes are not involved in hyphenation; it is the
\lccode table that matters there. Read Appendix H.
And anyway, hyphenation is irrelevant to italic corrections. And we are
talking about use of i.c. in math, not text (as Dan explained at some
length), and, finally there is nothing to be done. The catcode
assignments just have to be taken out of lua(la)tex format files, and
those chars can unfortunately not be used in control sequence names as a
result. It seems to me.
karl